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Long-Term Operation Performance Of Medium-Deep Borehole Heat Exchangers In The Guanzhong Area, Zhang Zhibin, Ma Zhendi, Hao Jianke, Jia Guosheng, Ke Tingting, Cheng Chonghua, Jin Liwen

Coal Geology & Exploration

Technologies for heating utilizing medium-deep geothermal energy exhibit promising application prospects in the Guanzhong area of China, which boasts abundant geothermal resources. Geological parameters serve as determining factors in the performance of medium-deep borehole heating systems. This study aims to explore the performance of medium-deep borehole heating systems in the Guanzhong area, Shaanxi Province. First, this study analyzed the geological parameters of five typical areas in Guanzhong: Xingping City under the jurisdiction of Xianyang City, Weicheng District of Xianyang, and Gaoling, Huyi, and Chang’an districts of Xi’an City. Then, by combining the typical structural parameters of buried pipes, this study …

Influencing Factor Analysis And Optimization Of Heat Extraction Performance Of Moderately Deep Coaxial Borehole Heat Exchangers In Northern Shaanxi, China, Zou Haijiang, Li Yongpeng, Zhang Lin, Hui Peng, Liu Houning, Shen Fang, Wang Fenghao

Coal Geology & Exploration

The geothermal heating technology utilizing moderately deep coaxial borehole heat exchangers (MDCBHEs) has emerged and found extensive applications in urban heating in northern China. Despite abundant geothermal resources, northern Shaanxi exhibits slightly low geothermal gradients and distinct thermophysical properties of rocks and soils. Therefore, geological parameters influence the heat transfer performance of MDCBHEs in this area. Using OpenGeoSys, an open-source numerical simulation platform, this study established a three-dimensional calculation model for heat transfer between a MDCBHE and surrounding strata. Based on typical geological parameters in northern Shaanxi, the study investigated the influence of various design parameters on the heat transfer …

Statistical Analysis Of The Spatial Distribution And Genesis Of Lithium In Geothermal Water In The Yangbajing-Gulu Rift, Xizang, Chen Yakui, Kong Yanlong, Duan Jiabin, Sun Wenjie, Cheng Yuanzhi

Coal Geology & Exploration

In the Yangbajing-Gulu rift, located in Xizang, the lithium concentration in geothermal water exceeds the average level of thermal springs in Xizang. However, the hydrochemical genesis of lithium in geothermal water in this rift remains controversial, and one primary reason for this is the unclear spatial distribution pattern of lithium. Common methods for analyzing spatial distribution patterns include Ordinary Kriging and CO-Kriging. Nevertheless, the former suffers low precision. For the latter, it is difficult to obtain suitable auxiliary variables. Given this, this study determined two auxiliary variables: (1) the Cl⁻ concentration, a physicochemical parameter exhibiting the strongest correlation with …

Modelling Leucaena Biomass Under Rainfed Production Systems Of Semiarid Regions, M. J. D. Cândido, J. L. G. Santos, A. C. R. Cavalcante, S. R. Maranhão, M. A. Santos, J. M. Osorio Leyton

IGC Proceedings (1977-2023)

The climatic variability of semiarid regions is the main source of uncertainties associated with forage and animal production, indicating a need for tools that accurately estimate forage production in order to construct a forage budgeting plan for livestock. This study simulated the biomass of Leucaena (Leucaena leucocephala) using the PHYGROW model in four locations located in Brazilian Semiarid. The work was carried out based on field data collected from 2019 to 2021. After sowing in 2018, leucaena was harvested when it reached 200 cm and to a target residual height of 70 cm. The biomass (fresh matter) was …

Micro Mineral Concentrations Of Congo Grass As Affected By Shading And Harvesting Age, P. A. Dele, J. I. Akinyode, A. A. Eesuola, B. T. Akinyemi, F. E. Enwete, C. C. Anotaenwere, O. I. Awoola, O. L. Aiyesa

IGC Proceedings (1977-2023)

This study investigated the effect of levels of artificial shading and harvesting age on four micro mineral concentrations (iron, manganese, copper and zinc) of Congo grass (Brachiaria ruzizinensis Germain & Evrard). The experiment was a 3 x 3 factorial arrangement in a split plot design with four replicates, which is three levels of artificial shading (0, 30 and 60% shading) as the main plot and three harvesting age (3, 6 and 9 weeks after cutback). The grass was established in May 2017 and grazed in 2018 and 2019, but a cutback was done in May 2020 for this study …

Prospects For Improving Alfalfa Yield Using Genomic- And Phenomic-Based Breeding, M. W. Francis, D. Pap, A. Krill-Brown, E. C. Brummer

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa L.) is a perennial outcrossing legume that is cultivated as an important forage crop in many parts of the world. Yield is the most important trait for profitable alfalfa production, yet over the last 30 years yield improvement in California has stagnated. Current breeding methods focus on recurrent phenotypic selection; however, alternatives incorporating genomic- and phenomic-based information may enhance genetic gain and help to address the lack of yield improvement. Here we attempt to increase the yield potential of alfalfa using genomic selection (GS) in combination with high throughput phenotyping (HTP). A total of 193 families …

Improving Frost Seeding Accuracy With An Entry Level Gps Unit, B. L. Hendrix, Christopher D. Teutsch, J. Jackson, C. Raymond

IGC Proceedings (1977-2023)

Guidance utilizing GPS has long been used for various operations in row crop agriculture. However, the high cost of these systems has limited their use in low-input forage and livestock operations. Reduced prices and the availability of used guidance systems have the potential to increase the use of precision agriculture in pastoral settings. In the past, frost seeding often resulted in areas that received no seed and areas that were double seeded. The objective of this experiment was to evaluate the impact of using a guidance system on the uniformity of seed dispersal. This study was conducted at the University …

Looking At Cell Wall Components With Our Customers In Mind, D. J. Heuschele, Z. Xu, J. F. S. Lamb, H. J. Jung, D. A. Samac

IGC Proceedings (1977-2023)

Fiber digestibility of alfalfa for animal nutrition is a complex system encapsulating animal, plant, and microbe biological traits. Understanding all components within the system is key to predicting forage quality. We investigated the relationship between alfalfa cell wall components and invitro neutral detergent fiber digestibility (IVNDFD) speed (16-hr) and potential (96-hr) of by cattle ruminant microbes. A composite alfalfa (Medicago sativa L.) population from seven commercial cultivars underwent two cycles of bidirectional selection for plants with low or high stem 16-hr IVNDFD and low or high stem 96-hr IVNDFD. The resulting selected populations were then evaluated by near inferred spectrometry …

Review: Potential Of Using Seaweed Silage Inoculated With Lactic Acid Bacteria And Its Impact Towards Sustainable Animal Feed, Azziza Mala, Subha Bhassu, Norhidayah Mohd Taufek, Najiah M. Sadali, Siran Wang, Shao Tao, Elnour Mohamed, Adibi N, Nor

IGC Proceedings (1977-2023)

Since ancient times, seaweed has been used to supplement animal feed in coastal areas.

In recent years, there has been a growing demand for seaweed as an animal feed. Effective preservation methods are required because of annual variations in seaweed availability and biochemical composition. Ensiling could be an effective method to preserve seaweeds for animal feed applications. Using lactic acid bacteria is a substitute biological technique for keeping and restoring the usual physiological state of the animal and increasing efficiency. The aim of this review is the potential of using lactic acid bacteria as an inoculant for seaweed silage for …

Managing Interspecies Competition To Improve Spring Pasture, Kelly M. Mercier, Eric D. Billman, K. Soder, D. M. Jaramillo, Sarah C. Goslee, P. A. Adler

IGC Proceedings (1977-2023)

Orchardgrass (Dactylis glomerata L.) is one of the earliest maturing pasture grasses utilized in the northeastern United States. However, wet springs can delay forage harvesting resulting in advanced forage maturity and reduction in nutritive value. Chicory (Cichorium intybus L.) is a tall, upright-growing forb that shows promise as a high-energy companion crop to orchardgrass and may delay orchardgrass maturity through shading effects on plant morphology. The objective of this study was to evaluate monocultures and mixtures of orchardgrass, chicory, and white clover (Trifolium repens L.) over two consecutive springs to determine the effects of species diversity on …

Estimation Of Sugarcane Yield Using Multi-Temporal Sentinel 2 Satellite Imagery And Random Forest Regression, Alireza Taravat, Gebeyehu Abebe, Berhan Gessesse, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

Advancements in remote sensing techniques have greatly enhanced crop monitoring and yield estimation, with spectral vegetation indices (VIs) serving as a key component. Our study investigates the use of Sentinel-2 data, notable for its red-edge bands, in estimating sugarcane yield in Ethiopia's Awash Basin. Utilizing 22 VIs from S2 imagery, our approach combines Random Forest (RF) regression with the Recursive Feature Elimination (RFE) algorithm to improve the accuracy of sugarcane yield predictions. The results demonstrate the superior performance of the RF-RFE method over traditional RF with full datasets and Stepwise Multiple Regression (SMR). Particularly, VIs focusing on the red-edge spectral …

Investigation Of Earthquake Sequence And Stress Transfer In The Eastern Anatolia Fault Zone By Coulomb Stress Analysis, Hamdi̇ Alkan, Aydin Büyüksaraç, Özcan Bektaş

Turkish Journal of Earth Sciences

A devastating earthquake with a magnitude of (Mw = 7.7) occurred on February 06, 2023, in the Pazarcık segment of the Eastern Anatolian Fault Zone, which has not shown major earthquake activity for a long time. On the same day, another earthquake with a magnitude of (Mw = 7.6) occurred in Ekinözü-Elbistan (Kahramanmaraş) in the northwest. Three more earthquakes with magnitudes of Mw = 6.6, Mw = 5.9, and ML = 5.7 occurred on the same day, and significant damage, loss of life, and property occurred in 11 provinces and districts. A sixth earthquake occurred with Mw = 6.4 magnitude …

Preliminary Results Of The Great Kahramanmaraş 6 February 2023 Earthquakes (Mw 7.7 And 7.6) And 20 February 2023 Antakya Earthquake (Mw 6.4), Eastern Türkiye, Şule Gürboğa, Önder Kayadi̇bi̇, Hafi̇ze Akilli, Serap Arikan, Sevi̇lay Tan

Turkish Journal of Earth Sciences

The first MW 7.7 and second MW 7.6 Kahramanmaraş earthquakes were the strongest tectonic events in Eastern Türkiye since the MW 7.9 Erzincan earthquake in 1939. The first and second events occurred on the Pazarcık and Çardak segments of the East Anatolian Fault System, respectively. A subsequent significant earthquake of MW 6.4 occurred in the Antakya fault zone. We summarize preliminary earthquake data and share our previous field observations to better understand the mechanism and provide scientific consequences for future investigations and layout planning. After combining the field observations, kinematic analysis of fault surfaces, investigations of orthophotos, characteristics of mainshocks, …

Surface Rupture During The 6th Of February 2023 Mw 7.6 Elbistan-Ekinözü (Kahramanmaraş) Earthquake: Implications For Fault Rupture Dynamics Along The Northern Branch Of East Anatolian Fault Zone, Mustafa Softa, Fi̇kret Koçbulut, Eli̇f Akgün, Ercan Aksoy, Hasan Sözbi̇li̇r, Orhan Tatar, Volkan Karabacak, Çağlar Özkaymak, Mehmet Utku, Özkan Cevdet Özdağ, Recep Çakir, Ahmet Demi̇r, Gökhan Arslan

Turkish Journal of Earth Sciences

On the 6th of February 2023, Mw 7.7 Pazarcık (Kahramanmaraş) and Mw 7.6 Ekinözü (Kahramanmaraş) earthquakes that occurred in Türkiye are devastating earthquake series that filled the existing seismic gaps on East Anatolian Fault Zone on the same day. The first Mw 7.7 earthquake caught most people in their sleep and 9 h later, a second one was triggered, ending up with more than 50k death toll, widespread damage to buildings, and massive landslides. This study presents the surface rupture geometry and coseismic displacement characteristics determined with field observations immediately after February 6, 2023, Ekinözü (Kahramanmaraş, Türkiye) earthquake (Mw 7.6). …

Tepehan Rockslide: A Large-Scale Earthquake-Induced Geological Structure Formed By Mw:7.8 Kahramanmaraş (Pazarcık) Earthquake, Türkiye, Ökmen Sümer

Turkish Journal of Earth Sciences

Three devastating and powerful earthquakes hit the southeastern and eastern parts of Turkey and the northestern part of Syria in February of 2023, causing many earthquake-induced slope movements. One of these major mass movements is called the “Tepehan Rockslide”, which was formed by the first Mw: 7.8 earthquake on February 6th, 2023 at Pazarcık (Kahramanmaraş) located in the Altınözü district of Hatay province. The rockslide involved the movement of Middle Miocene basement rocks that consist of clayey limestone, marl, and fine-grained clastic sedimentary rocks. The morphogenetic evaluation of the structure reveals that the Tepehan Rockslide is a very rapidly developed …

Response Of Water Resources To The Kahramanmaraş Earthquakes (Mw 7.7 And Mw 7.6) That Occurred On February 6, 2023, On The East Anatolian Fault Zone (Türkiye), Celaletti̇n Şi̇mşek, Görkem Akinci, Okan Fistikoğlu, Kerem Canli, Hasan Sözbi̇li̇r, Azi̇ze Ayol, Efem Bi̇lgi̇ç

Turkish Journal of Earth Sciences

On February 6, 2023, two destructive earthquakes of 7.7 MW and 7.6 MW occurred in Pazarcık (Kahramanmaraş) and Elbistan (Kahramanmaraş) at 04:17 and 13:24 hours, respectively. These earthquakes caused a surface rupture with a total length of 450 km in the region with an average displacement of 3 m between the Arabian and Anatolian plates. This study was conducted to investigate the physical deformation of the aquifer system and the current water quality characteristics in the affected region utilizing field observations and on-site analysis of water sources and tap water. The study revealed significant physical changes in the karstic springs …

Soil Liquefaction And Subsidence Disaster In İskenderun Related To The 6 February 2023 Pazarcık (Mw: 7.7) And 20 February Defne (Mw: 6.4) Earthquakes, Türkiye, Hüseyi̇n Öztürk, Craig A. Davis, İbrahi̇m Kuşku, Süleyman Dalğiç, Cem Kasapçi, Muharrem Alper Şengül

Turkish Journal of Earth Sciences

The Mw 7.7 Pazarcık earthquake on February 06, 2023, struck southern Türkiye, causing typical liquefaction along the shores of İskenderun Bay. This liquefaction was characterized by lateral spreading, subsidence, and flooding. Subsidence-triggered sand ejecta, water flows, and opening cracks were identified in areas spanning approximately 2 km in length and 300 m in width. Based on coastal references such as lighthouses or harbor platforms, settlements of 0.8 m and lateral spreading of 0.4% were recorded along the coastal zone following the Pazarcık earthquake. According to camera recordings, liquefaction-related water and silty sand outflows occurred 29 min after the earthquake. The …

Assessing Sediment Migration And Salmonid Habitat Recovery Following A Small Dam Removal And A Flood, Mill Creek, California, Usa, Madeline C. Doyle

Master's Theses

In 2021, the lower Mill Creek Dam (~4 m tall, ~8 m wide) was removed from the Mill Creek-San Vicente Creek watershed (18 km2), located in the Santa Cruz Mountains. Topographic surveys and pebble counts were performed at 27 transects four times between 2021 and 2023 to compare changes in channel characteristics and grain size to document the response to a small dam removal and the transition between drought and flood conditions. The goals of this study were to: (1) describe the movement of impounded sediment; (2) assess the success of habitat restoration for two endangered anadromous fish species: coho …

Geologists As Colonial Scouts: The Rogers Expedition To Otavi And Tsumeb, Namibia, 1892–1895, Selby Hearth

Geology Faculty Research and Scholarship

From 1892 to 1895, the South West Africa Company (SWACO) expedition led by geologist Matthew Rogers conducted the first geologic mapping in Namibia’s Otavi Mountains, including the now world-famous Tsumeb Mine. This paper uses archival documents from the Rogers expedition to trace his geologic contributions and to illustrate important themes in the relationships between 19th century colonial geologists, Western colonizing governments, Indigenous communities, resource extraction, and corporations. To carry out his mapping, Rogers performed a continuous balancing act between British and German colonial powers and local African leaders. The local leaders and communities he interacted with variously resisted his incursions, …

Cataloguing Minerals, Part One: Historical Cataloguing Practices And The Logics Of Colonialism, Selby Hearth, Carrie Robbins, Marianne Weldon, Aha Anderson, Rosa Bieber-Stanley, April Chernila, Helen Christ, Hannah Cosgrove, Morgan Hanson-Rosenberg, Carly Hill, Maya Hofstetter, Emily Lazo, Izzie Ludlow, Samantha Lyster, Rachel Myers, Jasper Nash, Georgia Reed, Julia Saint- Amour

Geology Faculty Research and Scholarship

Mineral wealth has motivated and funded extractive empires, often at the expense of local communities, workers, natural environments, and public health. Yet those connections are not recorded in traditional mineral catalogues, which divorce specimens from context. This article examines the roots of those omissions and situates mineral cataloguing in the larger body of literature on knowledge organization systems and their relation to power. We examine how colonial ideologies of land and people become entrenched in mineral cataloguing practices, and how this reinforces the ways that contemporary geologists think about their work. We argue that revising mineral cataloguing practices is a …

Atmospheric And Earth Science 498 Professsional Development, Tess Olten, Robert Griffin

Open Educational Resources (OER)

Whether you're already in the workforce, or you're still in school and haven't yet applied for your first position -- the job application process can be both exciting and demoralizing. Sometimes, finding a new job feels like a full-time job itself -- especially when the competition is steep and the field of candidates is crowded.

How can you help yourself stand out from other applicants and land the job of your dreams? In this course, you'll work through each step of the application process, as well as consider graduate school as an alternative or additional choice. First, you'll explore tips …

Why Is Grant Lake A Reservoir? A Brief Geological And Human History, From The Pleistocene To The Present, Robert B. Marks

Eastern Sierra History Journal

Drawing on a range of archival resources and illustrative material, Prof. Marks probes why and how Grant Lake in the Eastern Sierra of California became a reservoir. The process is long and involved, and has much to do with a remote and ancient lake ultimately being developed to serve the water needs of the distant city of Los Angeles.

Adsorption Of Perfluoroalkyl Substances With Activated Carbon: Characterizing Non-Hazardous Simulants, Jennifer Hensley

Browse all Theses and Dissertations

Per- and polyfluoroalkyl substances (PFAS) are of great interest recently because some members of this class exhibit human health risks at extremely low levels, making them the current subject of proposed regulation and policy. Treatment of PFAS contaminated wastewater often is performed through adsorptive processes, e.g., with activated carbon. Due to complexities with PFAS laboratory analysis, assessing treatment efficacy through direct measurement of PFAS is expensive and time consuming, potentially delaying the design and implementation of site-specific treatment systems. This project identified and characterized potential suitable simulants for PFAS during wastewater treatment for which analysis can be timely and economical. …

Water-Level And Recoverable Water In Storage Changes, High Plains Aquifer, Predevelopment To 2019 And 2017 To 2019, Virginia L. Mcguire, Kellan R. Strauch

United States Geological Survey: Water Reports and Publications

The High Plains aquifer underlies 111.8 million acres (about 175,000 square miles) in parts of eight States: Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial groundwater irrigation (about 1950). This report presents water-level changes and change in recoverable water in storage in the High Plains aquifer from predevelopment (about 1950) to 2019 and from 2017 to 2019.

Water-level changes from predevelopment to 2019, by well, ranged from a rise of 86 feet to a decline of 265 feet; the range for …

Nanoscale Studies Of Magnesium Carbonate Precipitation At Ambient Conditions, Ian Shortt

Material Science and Engineering Dissertations - Archive

Currently approximately 8% of global greenhouse gas emissions can be attributed to the construction industry; of these emissions, a little over half of these emissions are due to the production of traditional calcium-based cements. Magnesium carbonate cements present a promising alternative to traditional calcium-based cements, both in terms of emission reductions and in terms of strength. The primary drawback to magnesium carbonate cements is that ambient curing is not yet viable. The objective of this dissertation is to therefore develop greater understanding of the precipitation pathways undertaken by hydrated magnesium carbonates under near-ambient conditions. In the first section of this …

Critical Convergence: Mapping The Boundaries Of How Faculty Interrogate Whiteness In The Geoscience Educational Landscape, James E. Hobbs

Educational Leadership & Policy Studies Dissertations - Archive

This study examined the role of faculty members in interrogating whiteness within geoscience education. The dominant reliance on whiteness as the primary way of knowing in geoscience education has long perpetuated a singular perspective that serves as a mechanism for reinforcing existing power structures rooted in white supremacy. Drawing on tenets from Critical whiteness Studies, Curriculum Theory, and Transformative Learning Theory, this research investigated U.S. higher education faculty members' strategies and challenges in disrupting whiteness within the geoscience curriculum.

Through critical qualitative narrative inquiry, data were collected through semi-structured interviews with geoscience faculty members across multiple institutions across the United …

A Field-Based Study Of Dust Emissivity In The Northern Chihuahuan Desert, U.S.: Testing The Preferential Dust Source Scheme, Gwenn L Harsha

Dissertations and Theses

We characterized spatiotemporal dust emissivity in the Northern Chihuahuan Desert (New Mexico, Texas, and Arizona, U.S.) using the Portable In-Situ Wind Erosion Lab (PI-SWERL) and measurements of soil crust strength, soil texture and soil moisture. Field-based measurements of emissivity were compared to the results of the Preferential Dust Source (PDS) scheme (Bullard et al., 2011) in the Chihuahuan Desert (Baddock et al., 2011) where 48% of satellite-observed plumes were sourced from ephemeral and dry lakes. Six landforms were tested: 1) ephemeral and 2) dry lake, 3) high and 4) low relief alluvial, and aeolian 5) sand sheet and 6) dunes. …

Can Phytoremediation-Induced Changes In The Microbiome Improve Saline/Sodic Soil And Plant Health?, Achal Neupane, Duncan Jukubowski, Douglas Fiedler, Liping Gu, Sharon A. Clay, David E. Clay, Shin-Yi Marzano

Agronomy, Horticulture and Plant Science Faculty Publications

Increasing soil salinity and/or sodicity is an expanding problem in the Northern Great Plains (NGP) of North America. This study investigated the impact of phytoremediation on the soil microbiome and if changes, in turn, had positive or negative effects on plant establishment. Amplicon sequencing and gas chromatograph/mass spectrometer analysis compared root metabolites and microbial composition of bulk vs. rhizosphere soils between two soil types (productive and saline/sodic). Beta-diversity analysis indicated that bacterial and fungal communities from both the bulk and rhizosphere soils from each soil type clustered separately, indicating dissimilar microbial composition. Plant species also influenced both root-associated bacterial and …

Cats, Dogs, And Roll Waves, John Adam

Mathematics & Statistics Faculty Publications

This article discusses the phenomenon of roll waves, which are shock-like patterns separated by smooth profiles that occur in flood waves. The author mentions that in a steady-state situation, the drag forces on the water in the channel are balanced by the down-slope gravitational force. The article also includes questions for readers to estimate the speed and length of the roll waves, as well as determine the stability of the flow. The author provides additional information about the Chezy formula, an empirical equation used in fluid mechanics to estimate the mean flow velocity of open channel flow.

Probable Extirpation Of The Jackrabbit (Lepus Californicus) From Arkansas, D.B. Sasse

Journal of the Arkansas Academy of Science

The black-tailed jackrabbit (Lepus californicus) was first documented in Arkansas during the modern era in Franklin County in 1927. Over the next few decades records were reported from multiple counties in northwest Arkansas and the species was locally common in Benton, Crawford, and Washington counties in the 1950s. The last Arkansas record documented in the scientific literature was from 1968 and since then there have only been three credible reports, with the last being from the late 1980s. The Arkansas Game and Fish Commission solicited reports of jackrabbits from the public and failed to find evidence of them from a …